This new invention proposes a pump and measuring device for coffee machines in particular which uses electronics to control the movement of the pump piston and which at the same time measures out the amount of water. More precisely, the pump is made of a cylinder with a piston inside which sucks the water from a tank and pumps it along an exit duct. These movements are controlled by an electronic or electromechanical device for measuring the exact amount of water to be pumped.
The device is particularly useful for small household electrical appliances, especially--though not exclusively--in coffee machines, allowing the machine to be made smaller and costing less to produce. Small electrical household appliances are well-known in which there is a device for pumping liquid that can also measure out the quantity of liquid pumped and heat it up. In these machines the various devices are autonomous and separate, particularly the pumping and measuring parts. Thus, for example, pumping may occur through a membrane pump with the water heated and measured out externally. This means that the output has to be controlled by the user or by a separate measuring device. The problems this causes are then reflected in the price and the size of the machine, both of which it would be beneficial to reduce.